System and method for monitoring a turbomachine with anomaly detection corrected by a wear factor

Abstract

A system for monitoring the state of health of a monitored aircraft engine comprises an anomaly detection unit which analyses engine operating parameters and raises an alarm if a result of the analysis of one of the engine operating parameters crosses a threshold, the alarm being associated with a probability of a given type of engine damage occurring. The system further comprises an engine operating conditions monitoring unit which determines a state of wear of the engine, and an alarm corroboration unit which weights the said probability of occurrence by the determined state of wear. The invention is applicable to the preventive maintenance of turbomachines.

What is claimed is: 
     
       1. A health monitoring system for an aircraft engine, comprising:
 an anomaly detection unit configured to analyse operating parameters of the aircraft engine and raise an alarm in case of threshold exceedance by an analysis result of one of the operating parameters of the aircraft engine, the alarm being associated with a probability of occurrence of a given degradation type of the aircraft engine; 
 an engine operating condition monitoring unit configured to determine an engine wear rate; and 
 an alarm confirmation unit configured to weight said probability of occurrence with the determined engine wear rate. 
 
     
     
       2. The health monitoring system according to  claim 1 , wherein the anomaly detection unit is configured to raise an alarm if an analysis result of one of the operating parameters of the aircraft engine complies with a threshold exceedance confirmation rule. 
     
     
       3. The health monitoring system according to  claim 2 , wherein the threshold exceedance confidence rule corresponds to the detection of a threshold exceedance during k operating cycles during the lifetime of the aircraft engine, k being a positive integer. 
     
     
       4. The health monitoring system according to  claim 2 , wherein the threshold exceedance confidence rule corresponds to the detection of a threshold exceedance during k successive operating cycles of the aircraft engine, k being a positive integer. 
     
     
       5. The health monitoring system according to  claim 2 , wherein the threshold exceedance confidence rule corresponds to the detection of a threshold exceedance on k operating cycles among n successive operating cycles of the aircraft engine, k and n being positive integers, n being higher than k. 
     
     
       6. The health monitoring system according to  claim 1 , wherein the engine operating condition monitoring unit is configured to determine the age of the aircraft engine since the aircraft engine has been first operated and deduce therefrom a nominal mode wear rate, to determine the time spent by the aircraft engine under critical operating conditions since the aircraft engine has been first operated and deduce therefrom a degraded mode wear rate, and to deduce the engine wear rate by combining the degraded mode wear rate with the nominal mode wear rate. 
     
     
       7. The health monitoring system according to  claim 6 , wherein the critical operating conditions comprise at least one operation among an operation outside a nominal temperature range, an operation outside a nominal hygrometry range, an operation outside a nominal pressure range and an operation in contact with corrosive products. 
     
     
       8. The health monitoring system according to  claim 1 , wherein the aircraft engine is a turbomachine. 
     
     
       9. A method for monitoring the health of an aircraft engine, comprising:
 a step of detecting anomalies which includes an analysis of operating parameters of the aircraft engine and an alarm raising in case of threshold exceedance by an analysis result of one of the operating parameters of the aircraft engine, the alarm being associated with a probability of occurrence of a given degradation type of the aircraft engine, 
 a step of monitoring operating conditions of the aircraft engine during which an engine wear rate is determined, and 
 an alarm confirmation step during which said probability of occurrence is weighted with the determined engine wear rate. 
 
     
     
       10. A non-transitory computer-readable medium comprising program code instructions for executing the steps of the method according to  claim 9 , when said program code instructions are run on a computer.